Which of the following statements is an example of a SELF JOIN?

A) SELECT department_id, department_name,location_id, city FROM departments NATURAL JOIN locations;
B) SELECT e.employee_id, e.last_name, e.department_id, d.department_id, d.location_id FROM employees e JOIN departments d ON (e.department_id = d.department_id);
C) SELECT e.employee_id, e.last_name, e.department_id, d.department_id, d.location_id FROM employees e JOIN departments d ON (e.department_id = d.department_id) AND e.manager_id = 149 ;
D) SELECT worker.last_name emp, manager.last_name mgr FROM employees worker JOIN employees manager ON (worker.manager_id = manager.employee_id);

D) SELECT worker.last_name emp, manager.last_name mgr FROM employees worker JOIN employees manager ON (worker.manager_id = manager.employee_id);

Computer Science & Information Technology

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